Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers identify protein that regulates killer cells

21.06.2002


Researchers at the University of Toronto and Mount Sinai Hospital have identified a protein that plays a critical role in the regulation of "natural killers cells" in the immune system’s battle against foreign and diseased cells.



"Our research is a small part of the larger problem of how viruses and diseased cells ravage the body and circumvent our immune system," says Kathleen Binns, a U of T doctoral student in medical genetics and microbiology and an author on a paper in the June 20 issue of Science.

Using mass spectrometry, Binns, who does research in the Samuel Lunenfeld Research Institute at Mount Sinai and MDS Sciex, sequenced and identified a mystery protein from co-researchers at the Swiss Federal Institute of Technology in Switzerland.


Once identified, the protein (SSPase) was sent back to the Swiss researchers where they cloned its gene and sequenced its DNA. That gene, they discovered, is a key component involved in regulation of "natural killer cells" - cells produced by the body’s immune system that attack foreign or mutated cells like caused by viruses or cancer.

"This research gives us a better understanding of how the immune system works. As a result, we have a better understanding of how viruses and cancer try to get around this process. One day, we will hopefully be able to develop treatments and therapies to counter these rogue cells," says Binns.

A group of genes called the major histocompatibility complex I (MHC-I) are a natural part of the immune system and present in most cells in the body, explains Binns. Acting like an information relay, the MHC-I molecules retrieve bits and pieces of the proteins from inside the cell and display them on the cell surface. "MHC complexes essentially give a read out of what’s inside the cell," she says.

T-cells, one of the main components of the immune system, "examine" the protein fragments on the cell surface and if they recognize them, the T-cells move on. If, however, the T-cells do not recognize the fragments, the cell may be hosting a virus or manufacturing mutant proteins (as in the case of cancer). The T-cells then react by attacking and killing the "diseased" cells.

Some virus and tumor cells, however, have evolved mechanisms that circumvent the T-cell attack by stopping MHC production and the display of disease proteins, says Binns.

As a countermeasure, the researchers found that the immune system developed a monitor that employs the SSPase protein and uses a second type of immune cell known as a natural killer cell, she notes. The protein processes MHC-I molecules to make a peptide signal. If sufficient levels of the MHC-I protein are present in the cell, the natural killer cell moves on. If, however, the killer cell detects insufficient levels of the MHC-I protein because it has not received the particular peptide signal, the killer cell attacks and destroys the suspect cell.

"This process is a check on viruses and abnormal cells that try to bypass the T-cell system," says Binns. "Viruses become smarter, our immune systems work to counteract them and the viruses get smarter again. There’s this constant evolution for the drive to survive, and viruses and cancer cells have the same drive to survive that we do."

Binns conducted the research with Andreas Weihofen, lead author on the study, Marius Lemberg and Bruno Martoglio of the Institute of Biochemistry at the Swiss Federal Institute of Technology, and Keith Ashman, an investigator at the Samuel Lunenfeld Research Institute at Mount Sinai Hospital.

This research was funded by the Natural Science and Engineering Research Council of Canada and MDS Sciex, the Swiss Federal Institute of Technology and the Swiss National Science Foundation.


CONTACT:

Kathleen Binns
Department of Medical Genetics and Microbiology
416-586-4524
binns@mshri.on.ca

Janet Wong
U of T Public Affairs
416-978-5949
jf.wong@utoronto.ca




Janet Wong | EurekAlert!

More articles from Life Sciences:

nachricht New insight into a central biological dogma on ion transport
26.06.2017 | Aarhus University

nachricht UK chemistry researchers develop catalyst that mimics the z-scheme of photosynthesis
26.06.2017 | University of Kentucky

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

New 3-D model predicts best planting practices for farmers

26.06.2017 | Agricultural and Forestry Science

New research reveals impact of seismic surveys on zooplankton

26.06.2017 | Life Sciences

Correct connections are crucial

26.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>